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  1. 06 12月, 2012 1 次提交
  3. 06 5月, 2012 1 次提交
  5. 08 4月, 2012 2 次提交
  7. 26 9月, 2011 2 次提交
    • P
      KVM: PPC: Assemble book3s{,_hv}_rmhandlers.S separately · 177339d7
      由 Paul Mackerras 提交于 
      This makes arch/powerpc/kvm/book3s_rmhandlers.S and
arch/powerpc/kvm/book3s_hv_rmhandlers.S be assembled as
separate compilation units rather than having them #included in
arch/powerpc/kernel/exceptions-64s.S.  We no longer have any
conditional branches between the exception prologs in
exceptions-64s.S and the KVM handlers, so there is no need to
keep their contents close together in the vmlinux image.

In their current location, they are using up part of the limited
space between the first-level interrupt handlers and the firmware
NMI data area at offset 0x7000, and with some kernel configurations
this area will overflow (e.g. allyesconfig), leading to an
"attempt to .org backwards" error when compiling exceptions-64s.S.

Moving them out requires that we add some #includes that the
book3s_{,hv_}rmhandlers.S code was previously getting implicitly
via exceptions-64s.S.
Signed-off-by: NPaul Mackerras <paulus@samba.org>
Signed-off-by: NAlexander Graf <agraf@suse.de>
      177339d7
    • A
      KVM: PPC: Add PAPR hypercall code for PR mode · 0254f074
      由 Alexander Graf 提交于 
      When running a PAPR guest, we need to handle a few hypercalls in kernel space,
most prominently the page table invalidation (to sync the shadows).

So this patch adds handling for a few PAPR hypercalls to PR mode KVM. I tried
to share the code with HV mode, but it ended up being a lot easier this way
around, as the two differ too much in those details.
Signed-off-by: NAlexander Graf <agraf@suse.de>

---

v1 -> v2:

  - whitespace fix
      0254f074
  9. 12 7月, 2011 5 次提交
    • P
      KVM: PPC: Allocate RMAs (Real Mode Areas) at boot for use by guests · aa04b4cc
      由 Paul Mackerras 提交于 
      This adds infrastructure which will be needed to allow book3s_hv KVM to
run on older POWER processors, including PPC970, which don't support
the Virtual Real Mode Area (VRMA) facility, but only the Real Mode
Offset (RMO) facility.  These processors require a physically
contiguous, aligned area of memory for each guest.  When the guest does
an access in real mode (MMU off), the address is compared against a
limit value, and if it is lower, the address is ORed with an offset
value (from the Real Mode Offset Register (RMOR)) and the result becomes
the real address for the access.  The size of the RMA has to be one of
a set of supported values, which usually includes 64MB, 128MB, 256MB
and some larger powers of 2.

Since we are unlikely to be able to allocate 64MB or more of physically
contiguous memory after the kernel has been running for a while, we
allocate a pool of RMAs at boot time using the bootmem allocator.  The
size and number of the RMAs can be set using the kvm_rma_size=xx and
kvm_rma_count=xx kernel command line options.

KVM exports a new capability, KVM_CAP_PPC_RMA, to signal the availability
of the pool of preallocated RMAs.  The capability value is 1 if the
processor can use an RMA but doesn't require one (because it supports
the VRMA facility), or 2 if the processor requires an RMA for each guest.

This adds a new ioctl, KVM_ALLOCATE_RMA, which allocates an RMA from the
pool and returns a file descriptor which can be used to map the RMA.  It
also returns the size of the RMA in the argument structure.

Having an RMA means we will get multiple KMV_SET_USER_MEMORY_REGION
ioctl calls from userspace.  To cope with this, we now preallocate the
kvm->arch.ram_pginfo array when the VM is created with a size sufficient
for up to 64GB of guest memory.  Subsequently we will get rid of this
array and use memory associated with each memslot instead.

This moves most of the code that translates the user addresses into
host pfns (page frame numbers) out of kvmppc_prepare_vrma up one level
to kvmppc_core_prepare_memory_region.  Also, instead of having to look
up the VMA for each page in order to check the page size, we now check
that the pages we get are compound pages of 16MB.  However, if we are
adding memory that is mapped to an RMA, we don't bother with calling
get_user_pages_fast and instead just offset from the base pfn for the
RMA.

Typically the RMA gets added after vcpus are created, which makes it
inconvenient to have the LPCR (logical partition control register) value
in the vcpu->arch struct, since the LPCR controls whether the processor
uses RMA or VRMA for the guest.  This moves the LPCR value into the
kvm->arch struct and arranges for the MER (mediated external request)
bit, which is the only bit that varies between vcpus, to be set in
assembly code when going into the guest if there is a pending external
interrupt request.
Signed-off-by: NPaul Mackerras <paulus@samba.org>
Signed-off-by: NAlexander Graf <agraf@suse.de>
      aa04b4cc
    • D
      KVM: PPC: Accelerate H_PUT_TCE by implementing it in real mode · 54738c09
      由 David Gibson 提交于 
      This improves I/O performance for guests using the PAPR
paravirtualization interface by making the H_PUT_TCE hcall faster, by
implementing it in real mode.  H_PUT_TCE is used for updating virtual
IOMMU tables, and is used both for virtual I/O and for real I/O in the
PAPR interface.

Since this moves the IOMMU tables into the kernel, we define a new
KVM_CREATE_SPAPR_TCE ioctl to allow qemu to create the tables.  The
ioctl returns a file descriptor which can be used to mmap the newly
created table.  The qemu driver models use them in the same way as
userspace managed tables, but they can be updated directly by the
guest with a real-mode H_PUT_TCE implementation, reducing the number
of host/guest context switches during guest IO.

There are certain circumstances where it is useful for userland qemu
to write to the TCE table even if the kernel H_PUT_TCE path is used
most of the time.  Specifically, allowing this will avoid awkwardness
when we need to reset the table.  More importantly, we will in the
future need to write the table in order to restore its state after a
checkpoint resume or migration.
Signed-off-by: NDavid Gibson <david@gibson.dropbear.id.au>
Signed-off-by: NPaul Mackerras <paulus@samba.org>
Signed-off-by: NAlexander Graf <agraf@suse.de>
      54738c09
    • P
      KVM: PPC: Handle some PAPR hcalls in the kernel · a8606e20
      由 Paul Mackerras 提交于 
      This adds the infrastructure for handling PAPR hcalls in the kernel,
either early in the guest exit path while we are still in real mode,
or later once the MMU has been turned back on and we are in the full
kernel context.  The advantage of handling hcalls in real mode if
possible is that we avoid two partition switches -- and this will
become more important when we support SMT4 guests, since a partition
switch means we have to pull all of the threads in the core out of
the guest.  The disadvantage is that we can only access the kernel
linear mapping, not anything vmalloced or ioremapped, since the MMU
is off.

This also adds code to handle the following hcalls in real mode:

H_ENTER       Add an HPTE to the hashed page table
H_REMOVE      Remove an HPTE from the hashed page table
H_READ        Read HPTEs from the hashed page table
H_PROTECT     Change the protection bits in an HPTE
H_BULK_REMOVE Remove up to 4 HPTEs from the hashed page table
H_SET_DABR    Set the data address breakpoint register

Plus code to handle the following hcalls in the kernel:

H_CEDE        Idle the vcpu until an interrupt or H_PROD hcall arrives
H_PROD        Wake up a ceded vcpu
H_REGISTER_VPA Register a virtual processor area (VPA)

The code that runs in real mode has to be in the base kernel, not in
the module, if KVM is compiled as a module.  The real-mode code can
only access the kernel linear mapping, not vmalloc or ioremap space.
Signed-off-by: NPaul Mackerras <paulus@samba.org>
Signed-off-by: NAlexander Graf <agraf@suse.de>
      a8606e20
    • P
      KVM: PPC: Add support for Book3S processors in hypervisor mode · de56a948
      由 Paul Mackerras 提交于 
      This adds support for KVM running on 64-bit Book 3S processors,
specifically POWER7, in hypervisor mode.  Using hypervisor mode means
that the guest can use the processor's supervisor mode.  That means
that the guest can execute privileged instructions and access privileged
registers itself without trapping to the host.  This gives excellent
performance, but does mean that KVM cannot emulate a processor
architecture other than the one that the hardware implements.

This code assumes that the guest is running paravirtualized using the
PAPR (Power Architecture Platform Requirements) interface, which is the
interface that IBM's PowerVM hypervisor uses.  That means that existing
Linux distributions that run on IBM pSeries machines will also run
under KVM without modification.  In order to communicate the PAPR
hypercalls to qemu, this adds a new KVM_EXIT_PAPR_HCALL exit code
to include/linux/kvm.h.

Currently the choice between book3s_hv support and book3s_pr support
(i.e. the existing code, which runs the guest in user mode) has to be
made at kernel configuration time, so a given kernel binary can only
do one or the other.

This new book3s_hv code doesn't support MMIO emulation at present.
Since we are running paravirtualized guests, this isn't a serious
restriction.

With the guest running in supervisor mode, most exceptions go straight
to the guest.  We will never get data or instruction storage or segment
interrupts, alignment interrupts, decrementer interrupts, program
interrupts, single-step interrupts, etc., coming to the hypervisor from
the guest.  Therefore this introduces a new KVMTEST_NONHV macro for the
exception entry path so that we don't have to do the KVM test on entry
to those exception handlers.

We do however get hypervisor decrementer, hypervisor data storage,
hypervisor instruction storage, and hypervisor emulation assist
interrupts, so we have to handle those.

In hypervisor mode, real-mode accesses can access all of RAM, not just
a limited amount.  Therefore we put all the guest state in the vcpu.arch
and use the shadow_vcpu in the PACA only for temporary scratch space.
We allocate the vcpu with kzalloc rather than vzalloc, and we don't use
anything in the kvmppc_vcpu_book3s struct, so we don't allocate it.
We don't have a shared page with the guest, but we still need a
kvm_vcpu_arch_shared struct to store the values of various registers,
so we include one in the vcpu_arch struct.

The POWER7 processor has a restriction that all threads in a core have
to be in the same partition.  MMU-on kernel code counts as a partition
(partition 0), so we have to do a partition switch on every entry to and
exit from the guest.  At present we require the host and guest to run
in single-thread mode because of this hardware restriction.

This code allocates a hashed page table for the guest and initializes
it with HPTEs for the guest's Virtual Real Memory Area (VRMA).  We
require that the guest memory is allocated using 16MB huge pages, in
order to simplify the low-level memory management.  This also means that
we can get away without tracking paging activity in the host for now,
since huge pages can't be paged or swapped.

This also adds a few new exports needed by the book3s_hv code.
Signed-off-by: NPaul Mackerras <paulus@samba.org>
Signed-off-by: NAlexander Graf <agraf@suse.de>
      de56a948
    • P
      KVM: PPC: Split out code from book3s.c into book3s_pr.c · f05ed4d5
      由 Paul Mackerras 提交于 
      In preparation for adding code to enable KVM to use hypervisor mode
on 64-bit Book 3S processors, this splits book3s.c into two files,
book3s.c and book3s_pr.c, where book3s_pr.c contains the code that is
specific to running the guest in problem state (user mode) and book3s.c
contains code which should apply to all Book 3S processors.

In doing this, we abstract some details, namely the interrupt offset,
updating the interrupt pending flag, and detecting if the guest is
in a critical section.  These are all things that will be different
when we use hypervisor mode.
Signed-off-by: NPaul Mackerras <paulus@samba.org>
Signed-off-by: NAlexander Graf <agraf@suse.de>
      f05ed4d5
  11. 13 10月, 2010 1 次提交
  13. 01 8月, 2010 1 次提交
  15. 17 5月, 2010 3 次提交
  17. 25 4月, 2010 2 次提交
    • A
      KVM: PPC: Implement Paired Single emulation · 831317b6
      由 Alexander Graf 提交于 
      The one big thing about the Gekko is paired singles.

Paired singles are an extension to the instruction set, that adds 32 single
precision floating point registers (qprs), some SPRs to modify the behavior
of paired singled operations and instructions to deal with qprs to the
instruction set.

Unfortunately, it also changes semantics of existing operations that affect
single values in FPRs. In most cases they get mirrored to the coresponding
QPR.

Thanks to that we need to emulate all FPU operations and all the new paired
single operations too.

In order to achieve that, we use the just introduced FPU call helpers to
call the real FPU whenever the guest wants to modify an FPR. Additionally
we also fix up the QPR values along the way.

That way we can execute paired single FPU operations without implementing a
soft fpu.
Signed-off-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NAvi Kivity <avi@redhat.com>
      831317b6
    • A
      KVM: PPC: Add helpers to call FPU instructions · 963cf3dc
      由 Alexander Graf 提交于 
      To emulate paired single instructions, we need to be able to call FPU
operations from within the kernel. Since we don't want gcc to spill
arbitrary FPU code everywhere, we tell it to use a soft fpu.

Since we know we can really call the FPU in safe areas, let's also add
some calls that we can later use to actually execute real world FPU
operations on the host's FPU.
Signed-off-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NAvi Kivity <avi@redhat.com>
      963cf3dc
  19. 05 11月, 2009 1 次提交
  21. 10 9月, 2009 2 次提交
  23. 16 6月, 2009 1 次提交
    • M
      powerpc: Add configurable -Werror for arch/powerpc · ba55bd74
      由 Michael Ellerman 提交于 
      Add the option to build the code under arch/powerpc with -Werror.

The intention is to make it harder for people to inadvertantly introduce
warnings in the arch/powerpc code. It needs to be configurable so that
if a warning is introduced, people can easily work around it while it's
being fixed.

The option is a negative, ie. don't enable -Werror, so that it will be
turned on for allyes and allmodconfig builds.

The default is n, in the hope that developers will build with -Werror,
that will probably lead to some build breaks, I am prepared to be flamed.

It's not enabled for math-emu, which is a steaming pile of warnings.
Signed-off-by: NMichael Ellerman <michael@ellerman.id.au>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
      ba55bd74
  25. 24 3月, 2009 2 次提交
  27. 31 12月, 2008 4 次提交
  29. 15 10月, 2008 1 次提交
  31. 20 7月, 2008 1 次提交
  33. 27 4月, 2008 1 次提交